The invention relates to a method for manufacturing a curved surface multi-layer wiring board used for a conformal array antenna, and a method for confirming NC (numerical control) data used for laser exposure.
FIG. 19 is a flow chart of a conventional method for manufacturing a curved surface multi-layer wiring board. In FIG. 19, 107 is a laying-up process, 112 is an inner layer connection process.
FIG. 20(a) is a side sectional view for manufacturing a curved surface multi-layer wiring board. In FIG. 20, 21 is formation mould, 22 and 23 are standard pins and standard pin acceptance holes on the above formation mould 21 respectively, 25 are separation films, 27 are inner patterns, 31 are through-holes connecting the inner patterns 27 between the layers. 45 is a flat surface multi-layer wiring board arranged on the formation mould via separation film 25.
FIG. 20(b) is a view of a curved surface multi-layer wiring board manufactured by the method shown in FIG. 20(a). In FIG. 20(b), 32 are outer patterns connected to the through-holes 31. 45b is a curved surface multi-layer wiring board.
A method for manufacturing a curved surface multi-layer wiring board is described hereinafter using FIG. 19, FIG. 20(a) and FIG. 20(b).
At first, the laying-up process (Step 107) is explained using FIG. 19. Standard holes for positioning are perforated into the inner layer copper clad laminate 1 obtained by forming a copper film on the substrate of the epoxy or polyimide series resin, the outer layer single side copper clad laminate 3 and the prepreg 4 (Step 102). Then, after exposing the inner layer copper clad laminate 1, inner layer patterns 27 are formed by developing and etching processes (Step 103). After perforating the standard holes into the outer layer single side copper clad laminates 3 and the prepregs 4, they are laid-up (Step 106) and pressed in order to obtain a pressed laminate (Step 141).
An inner layer connection process (Step 112) is explained hereinafter using FIG. 19. After manufacturing the laminate, holes are perforated into the pressed laminate (Step 142). The walls of the holes are cleaned (Step 110), then the walls of the holes are plated (Step 111) for forming through-holes 31.
An outer layer pattern 32 is then formed on the outer layer for making a flat multi-layer wiring board 45 by an exposure and etching process (Step 143).
In FIG. 20(a), the flat multi-layer wiring board 45 is set up on the formation mould 21 by aligning the standard pins 22 to the standard pin acceptance holes 23 through the hole in the flat multi-layer wiring board 45. The separation films 25 are put between the formation mould 21 and the flat multi-layer wiring board 45, then the flat multi-layer wiring board 45 is pressed by applying heat and a curved surface multi-layer wiring board 45b is obtained as shown in FIG. 20(b) (Step 144).
In the conventional method for manufacturing a curved surface multi-layer wiring board, even if the positioning of the through-holes and lands or pattern width is very precisely manufactured, there are many problems in that the copper films of the through-holes and patterns are stripped or the copper patterns are shared by the surface stress of the board since the surface formation is executed by applying heat. Also, there are other problems in that a spring back occurs after forming the laminate since the wiring board is formed to a curved shape by applying the pressure. Accordingly, it is difficult to obtain a desired shape of the curved surface multi-layer wiring board.
Also, if the surface of the curved surface multi-layer wiring board is not a two dimensional curve such as a cylindrical curved surface but instead a three dimensional curved surface such as a partial globe, the land or the pattern position of the curved multi-layer wiring board can not be simulated from the flat wiring board since the wiring board is deformed by the temperature of the press process. Therefore the lands and patterns formed at the state of the flat wiring board are shifted from the theoretical position.
In addition, when the curve surface is of an arbitrary shape which has a sharp curve in two directions, such as in a semi-sphere, wrinkles and cracks can form on the conductor surface when the copper film is pressed. Consequently, it can be difficult to manufacture a curved surface multi-layering wiring circuit board having a deep drawing or sharply curved surface.